Database Window Field Attributes - Dynamic Lookup - Control
Display
Caption
Enter a caption to describe this field. This will appear on the database window form.
Hint
Enter a hint that will be displayed when the cursor hovers over the entry field on the database window form.
Database Field
Field
From the drop-down list choose the required database field. This list will only contain those fields that are valid for the field type chosen above.
However, it is recommended that you define a Table Relationship and then use the Data Source page to choose the appropriate relationship. This will automatically configure this child field correctly.
Field in layer table
This option is only visible if the particular database has the Table type PDB Layer Extra in the Database Table Structure. If this is the case the field drop-down list will contain appropriate field names from the LAYERS database table as well. Selecting one of those fields will cause this option to be automatically checked.
This option is required so that Impact can correctly store the data for fields in the LAYERS table. Also, so it can distinguish between a field with the same name being added to both the LAYERS and ONE_UP table, for example. When this option is checked the data is stored internally with the name LAYERS.L_FIELD rather than just L_FIELD as it would for ONE_UP columns.
Value cannot be modified (Read-only)
Switch this option on to make this field read-only.
Value is not required until drawing Save
Any non-nullable fields (see Can be empty in database entry windows on the Table Field form) can have this option set. This will allow you to close the database entry window even when nothing has been entered. However, you will not be allowed to save the project until something has been entered for this field.
Dynamic Lookup
Use full width Listbox
Switch this option on to use a wider listbox.
Database Window Field Attributes - Dynamic Lookup - Data Source
Use defined table relationship
If you choose this option then you can pick a pre-defined table relationship from the list.
Configure data source manually
Press the 
button to open the Connection Selector window. From here you can choose the required data source on which to perform the dynamic lookup.
Parent Table
Select the required database table from the chosen data source. The list will contain all tables of type Custom, Address or Contacts as defined in the Database Table Structure.
Parent Field
Select the required database table field from the chosen table. The list will only contain those fields that have been defined to be a unique index field.
Fields
Display Field(s)
Specify the value to be displayed from the parent table. This could be a single column name; U_LOG_NAME, U_NAME; SQL containing multiple columns that must result in a single column or include an AS alias. Example: CONCAT(A_DESCRPT, ': ', A_STREET1).
Sort Field(s)
Specify optional sort columns from the parent table. If no sorting is specified then the Display Field(s) will be used. Example: CS_NAME asc, CS_CODE desc.
Filters
Filter SQL
Enter a SQL statement that will be applied to the search on the Lookup Table. Example: CS_ACTIVE=1.
Child Filter Field
Filter records based on the current value of a field in the Database Window. Qualify LAYERS columns with a colon.
Parent Filter Field
Specify the field in the parent table that must match the value of the Child Filter Field.